1. Field of the Invention
This invention relates to restoring data and more particularly relates to restoring cluster server data at a volume-level.
2. Description of the Related Art
A data processing system may employ cluster servers for critical data processing tasks. Two or more servers may be configured as cluster servers. Each cluster server may monitor other cluster servers. If a first cluster server hangs or otherwise is unable to complete one or more tasks, a second cluster server may identify the problem and resume processing functions for the first cluster server.
Cluster servers often employ one or more cluster disks. The cluster disks may store data for each of the cluster servers. The storage capacity of the cluster disks may be divided among one or more logical volumes. The cluster disk logical volumes are referred to herein as source volumes.
The source volumes and cluster disks may employ a number of data locks and other safeguards to assure that data used by a first cluster server is not overwritten by a second cluster server. As a result, the plurality of cluster servers may share the source volumes and the cluster disks.
Because cluster servers typically perform critical tasks, a snapshot of the data stored on the source volumes is often backed up to one or more snapshot volumes. A plurality of snapshot instances may be stored on the snapshot volumes.
Occasionally, the cluster servers may require that data from a snapshot instance be restored to the source volumes. Unfortunately, because of the large numbers of discrete files and the large amount of data that must be restored, recovering data from the snapshot instance may be a lengthy process. Yet because of the critical nature of the tasks performed by the cluster server, a lengthy recovery process may be unacceptable.